{
  "id": "api:x402-42c64a035e93a2e9",
  "kind": "api",
  "name": "modelmarket.dev/x402/x402-check",
  "description": "Debug an x402 payment before you submit it — why does USDC answer invalid signature? Verifies the EIP-3009 transferWithAuthorization (EIP-712 signer, v, low s, validity window) and the seller's terms (payTo, amount, asset, network, bound nonce), and names the domain a failing signature was really made for, e.g. Base Sepolia's 'USDC' used for Base mainnet's 'USD Coin', the commonest reason an x402 payment reverts. Offline, deterministic, signed answer.",
  "category": "x402",
  "url": "https://modelmarket.dev/x402/x402-check",
  "price": null,
  "x402": true,
  "meta": {
    "network": "eip155:8453",
    "scheme": "exact",
    "pay_to": "0x1218ff36C5d2e3B6A565CdB1A8B1AcCFc606Ad0a",
    "method": "POST",
    "last_updated": "2026-10-24T21:33:52.409Z"
  },
  "trust": {
    "verified": true,
    "uptime_pct": 100,
    "latency_ms": 676,
    "checks": 1
  }
}